Reduction of aromatics cracking on alumina by pyridine adsorption

摘要

gamma-Alumina is often used as a support in large number of reactions and has also inherent uses of its own.When y-Alumina is used in catalytic reactions,undesirable side reactions such as cracking,isomerization and coke formation always exist.These give undesired products and lead to catalyst deactivation.Pyridine has been found to chemisorb readily on Lewis acidic sites.Monolayer chemisorptions even at ambient temperatures were observed.The steric effects of pyridine may be utilized.This is similar to bimodal pore distribution in which constrictions at the openings inhibit diffusion of large asphaltenic,coke producing molecules,whereas smaller reactants compounds have easy access.